What is the wave intensity formula for sound?

AI Thread Summary
The formula provided by the physics teacher for calculating intensity, I = 2*(pi)^2*A^2*P*F^2*V, is not commonly found in standard physics literature. Intensity is typically defined as power per unit area, with the simpler formula I = P/A being widely accepted. The discussion highlights confusion regarding the teacher's formula and its derivation, suggesting that it may relate to the intensity of a plane wave. For further understanding, users are directed to resources on intensity in mechanical waves. Clarification from the teacher on the formula's context and derivation is recommended for better comprehension.
CoolGod
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Our physics teacher gave us a formula to calculate intensity, she didn't really specify what intensity, it should be related to sound.
I = intensty
A = amplitude
P = Density
F = frequency
V = velocity
pi = 3.14
she said I = 2*(pi)^2*A^2*P*F^2*V
I can't find anything like this in books or internet, maybe I'm bad at searching.
I was wondering is she right and can she explain the formula? I get the simple I=P/A formula.
 
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This is the formula for the intensity of a plane wave with amplitude A, and frequency f, propagating with speed v.
You can find a complete derivation of the formula here

http://physics.info/intensity/

or just look up "intensity plane mechanical wave" or similar.
 
Formula to calculate intensity: I = V/A Where: I = intensity V = voltage A = area of the conductor Example: Calculate the intensity of the current in a 16 cm wire carrying a current of 2.0 A. Solution: I = V/A = 2 A = area of the conductor = 16 I = 2/16 = 0.125
 
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